diff --git a/accel/tcg/atomic_template.h b/accel/tcg/atomic_template.h index afa8a9daf3..d347462af5 100644 --- a/accel/tcg/atomic_template.h +++ b/accel/tcg/atomic_template.h @@ -28,8 +28,8 @@ # define SHIFT 4 #elif DATA_SIZE == 8 # define SUFFIX q -# define DATA_TYPE uint64_t -# define SDATA_TYPE int64_t +# define DATA_TYPE aligned_uint64_t +# define SDATA_TYPE aligned_int64_t # define BSWAP bswap64 # define SHIFT 3 #elif DATA_SIZE == 4 diff --git a/include/qemu/atomic.h b/include/qemu/atomic.h index fe5467d193..112a29910b 100644 --- a/include/qemu/atomic.h +++ b/include/qemu/atomic.h @@ -271,7 +271,19 @@ _oldn; \ }) -/* Abstractions to access atomically (i.e. "once") i64/u64 variables */ +/* + * Abstractions to access atomically (i.e. "once") i64/u64 variables. + * + * The i386 abi is odd in that by default members are only aligned to + * 4 bytes, which means that 8-byte types can wind up mis-aligned. + * Clang will then warn about this, and emit a call into libatomic. + * + * Use of these types in structures when they will be used with atomic + * operations can avoid this. + */ +typedef int64_t aligned_int64_t __attribute__((aligned(8))); +typedef uint64_t aligned_uint64_t __attribute__((aligned(8))); + #ifdef CONFIG_ATOMIC64 /* Use __nocheck because sizeof(void *) might be < sizeof(u64) */ #define qatomic_read_i64(P) \ diff --git a/include/qemu/stats64.h b/include/qemu/stats64.h index fdd3d1b8f9..802402254b 100644 --- a/include/qemu/stats64.h +++ b/include/qemu/stats64.h @@ -21,7 +21,7 @@ typedef struct Stat64 { #ifdef CONFIG_ATOMIC64 - uint64_t value; + aligned_uint64_t value; #else uint32_t low, high; uint32_t lock; diff --git a/linux-user/hppa/cpu_loop.c b/linux-user/hppa/cpu_loop.c index 3aaaf3337c..82d8183821 100644 --- a/linux-user/hppa/cpu_loop.c +++ b/linux-user/hppa/cpu_loop.c @@ -82,7 +82,7 @@ static abi_ulong hppa_lws(CPUHPPAState *env) o64 = *(uint64_t *)g2h(cs, old); n64 = *(uint64_t *)g2h(cs, new); #ifdef CONFIG_ATOMIC64 - r64 = qatomic_cmpxchg__nocheck((uint64_t *)g2h(cs, addr), + r64 = qatomic_cmpxchg__nocheck((aligned_uint64_t *)g2h(cs, addr), o64, n64); ret = r64 != o64; #else diff --git a/softmmu/timers-state.h b/softmmu/timers-state.h index 8c262ce139..94bb7394c5 100644 --- a/softmmu/timers-state.h +++ b/softmmu/timers-state.h @@ -47,7 +47,7 @@ typedef struct TimersState { int64_t last_delta; /* Compensate for varying guest execution speed. */ - int64_t qemu_icount_bias; + aligned_int64_t qemu_icount_bias; int64_t vm_clock_warp_start; int64_t cpu_clock_offset; diff --git a/util/qsp.c b/util/qsp.c index bacc5fa2f6..8562b14a87 100644 --- a/util/qsp.c +++ b/util/qsp.c @@ -83,8 +83,8 @@ typedef struct QSPCallSite QSPCallSite; struct QSPEntry { void *thread_ptr; const QSPCallSite *callsite; - uint64_t n_acqs; - uint64_t ns; + aligned_uint64_t n_acqs; + aligned_uint64_t ns; unsigned int n_objs; /* count of coalesced objs; only used for reporting */ }; typedef struct QSPEntry QSPEntry;